A guideway mounted vehicle receives information related to other vehicles along a same guideway through a control system. The control system provides information related to location and speed of the other vehicles and provides instructions for movement of the guideway mounted vehicle based on this location and speed information. The control system communicates this information through communication devices located along a wayside of the guideway.
The communication devices along the guideway act as relays between the control system and the guideway mounted vehicle. In order for information regarding the other vehicle to be received by the guideway mounted vehicle, the other vehicle first determines the information and then transmits the information to a wayside communication device. The wayside communication device transmits the information to the control system. The control system then transmits the information to another wayside device near the guideway mounted vehicle. The other wayside device then transmits the information to the guideway mounted vehicle. Such a system has at least five points of failure which could interrupt receipt of the information by the guideway mounted vehicle; each of the wayside communication devices, the control system, the other vehicle and the guideway mounted vehicle.
When one of the points of failure causes the information to be interrupted the guideway mounted vehicle would proceed to the end of a limit of movement authority (LMA) and stop to await further instructions or for a manual operator to arrive.